Nitric oxide (NO) is a simple gas with free radical properties. No one would have imagined a role for such a simple substance in the human body. In 1998, R. E Furchgott, E Murad, and L. J. Ignarro received the Nobel prize for their work on NO. Interestingly, Alfred B. Nobel, who invented dynamite by combining nitro­ glycerin with other substances, took nitroglycerin for his chest pain without realizing that NO mediates its action. Now, in addition to its vasodilating action, NO is known to possess many fundamental functions that include neurotrans­ mission, blood pressure control, blood clotting, and immune responses. These diverse functions, conversely, imply that the simple NO molecule may unite neuroscience, physiology, and immunology and may change our understanding of how cells communicate and defend themselves. In this context, the International Symposium, Nitric Oxide and Free Radicals, was organized to address current thinking about the widespread distribution and variety of functions of NO in the eye. The symposium was held in Kyoto, Japan, September 28-29 as a Satellite Symposium of the XII International Congress of Eye Research, 1996. The Symposium was the first international gathering of leading scientists and ophthalmologists meeting to present and discuss their most recent results in a specialized area of research, specifically concerning the eye.